Various packaging is produced with two or more chambers. This includes bottles, syringes, dispensing pumps and tubes. In most applications it is important that the components of the chambers not come into contract until the components are dispensed from the package. This is the case since in many instances the components are reactive. Consequently, the separating walls in the package must be of a high integrity. There cannot be any voids in the wall material. This then presents the problem with regard to determining if there are any voids in the walls of a finished package. Preferably this should be accomplished at an early stage so that time and materials are not expended in the manufacture of entire packages that may have defects in the material of the divider walls.
It has been found that the divider walls of packages, and in particular tube packages, can be tested as to integrity by electric potential testing techniques. A voltage potential is placed on an electrode on one side of the wall versus an electrode on the other side of the wall. The potential difference is adjusted so that the divider wall material insulates the electrodes, one from the other. However, if there is a void in the wall, there is a leak of current through the barrier void with a change in potential. This change in potential then can be measured and noted to reject the container with this void containing interior wall. This is a very effective technique for the testing of multichamber tubes, and in particular, dual chamber tubes. This is the case since the test technique can be incorporated into the process of making the tube. That is, the divider walls can be tested for voids after the manufacture of the tube body and prior to the full construction of the tube.